Christophe D'ivernois

Frequency of recurrent atrial fibrillation after catheter ablation of overt accessory pathways

The effect of successful catheter ablation of overt accessory pathways on the incidence of atrial fibrillation (AF) was studied in 129 symptomatic patients with (n = 75) or without (n = 54) previous documented AF. Fourteen had had ventricular fibrillation. Factors predictive of recurrence were examined, including electrophysiologic parameters. Atrial vulnerability was defined as induction of sustained AF (greater than 1 minute) using single, then double, atrial extrastimuli at 2 basic pacing cycle lengths. When compared to patients with only reciprocating tachycardia, patients with clinical AF included more men (77 vs 54%, p = 0.008) and were older (35 +/- 12 vs 29 +/- 12 years, p = 0.01). They had a significantly shorter cycle length leading to anterograde accessory pathway block (252 +/- 42 vs 298 +/- 83 ms, p less than 0.001), greater incidences of atrial vulnerability (89 vs 24%, p less than 0.001) and subsequent need for cardioversion (51 vs 15%, p less than 0.001). After discharge, the follow-up period was 35 +/- 12 months (range 18 to 76); 7 patients with previous spontaneous AF (9%) had recurrence at a mean of 10 months after ablation. Age, presence of structural heart disease accessory pathway location, atrial refractory periods and accessory pathway anterograde conduction parameters were not predictive of AF recurrence. Persistence of atrial vulnerability after ablation was the only factor associated with further recurrence of AF. Atrial vulnerability was observed after ablation in only 56% of patients with previous AF versus 89% before ablation. It is concluded that successful catheter ablation of accessory pathways prevents further recurrence of AF in 91% of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Catheter Ablation of Accessory Pathways: Technique and Results in 248 Patients

WARIN, J.‐F., ET AL.: Catheter Ablation of Accessory Pathways: Technique and Results in 248 Patients. Two hundred and forty‐eight patients with refractory arrhythmias related to an accessory pathway underwent catheter ablation. Cathodal shocks (I60 to 240 joules) were delivered through the distal electrode of a standard catheter (usually a quadripolar electrode catheter with 5‐mm interelectrode distances). A paddle electrode positioned opposite to the catheter served as the anode. Ablation of 24 right anteroseptal, 16 right parietal, 86 posteroseptal, 120 left parietal and four Mahaim pathways was clinically successful in eliminating symptomatic tachycardia in 236 patients (>96%) over a follow‐up of 3 to 64 months. There was no procedure‐related death but two patients developed a ventricular fibrillation at the fifth and seventh day, respectively. The latter led to a sudden death since this side effect occurred after discharge. There were no instances of systemic embolus but one pericardial effusion required subxiphoid needle drainage 6 weeks after the procedure. Other complications included: AV block in four patients with posteroseptal and in one with a right anterior septal pathway. In conclusion, a successful clinical outcome may be achieved in most patients. Catheter ablation is an important alternative to cardiac surgery and in our opinion represents first‐line treatment when therapy is required.

Distinctive response of arrhythmogenic right ventricular disease to high dose isoproterenol.

HAISSAGUERRE, M., ET AL.: Distinctive Response of Arrhythmogenic Right Ventricular Disease to High Dose Isoproterenol.Arrhythmogenic right ventricular disease is a potential cause of ventricular arrhythmias. Diagnosis is important due to the risk of sudden death, particularly as first symptom. Diagnosis is based on the angiographic demonstration of abnormal right ventricular morphology and function, while the sensitivity of noninvasive tests is relatively low. Following a particular observation studied in 1984, we prospectively assessed the diagnostic value of high dose isoproterenol infusion in 44 patients with an angiographically determined arrhythmogenic right ventricle. A continuous infusion of isoproterenol (8–30 µg/min) was administered during a 3‐minute period, regardless of the obtained heart rate. In a control group of 50 patients without structural heart disease, isoproterenol induced a monomorphic ventricular tachycardia salvo in only one patient (2%). In patients with an arrhythmogenic right ventricle, isoproterenol induced one or more ventricular tachycardia runs in 39/44 cases (88%): one triplet in three patients, several runs in 23 patients and a sustained ventricular tachycardia in 13 patients. Arrhythmia was polymorphous in 85% of cases, but left bundle branch block morphelogy was the predominant pattern. In conclusion, high dose isoproterenol is a highly sensitive test for the diagnosis of arrhythmogenic right ventricular disease.

Where are the left ventricular leads really implanted? A study of 90 consecutive patients.

Background: Cardiac resynchronization therapy (CRT) is a recognized treatment for severe heart failure. The recommended left ventricular (LV) lead position is at the lateral or posterolateral wall. However, LV leads cannot always be implanted at the expected site. The aim of our study was to describe in a large series of patients the anatomical position really achieved by LV leads at implant.

Fulguration for AV Nodal Tachycardia: Results in 42 Patients with a Mean Follow‐Up of 23 Months

HAISAGUERRE, M., ET AL.: Fulguration for AV Nodal Tachycardia: Results in 42 Patients with a Mean Follow‐Up of 23 Months. This report describes a catheter ablation technique to treat atrioventricular nodal reentrant tachycardia while preserving anterograde conduction, and its application in 42 patients with drug‐refractory repetitive episodes of tachycardia. One of these patients had common and reverse forms of tachycardia. Using atrial activation in the His‐bundle lead as a reference, the optimal ablation site was selected by positioning an electrode catheter to obtain a synchronous or earlier atrial activation than the reference during tachycardia. At this site, His‐bundle deflection was completely absent, or was present at a low amplitude (< 0.1 mV). In the majority of patients, these criteria were found in the immediate vicinity of the site of proximal His‐bundle recording (adjacent to the reference catheter). Shocks of 160 or 240 joules (J) were delivered at this site (mean ± SD = 518 ± 392 J/session) with a resulting preferential abolition of impairment of fast retrograde conduction. Anterograde conduction, though modified, was preserved in all patients, except for four (10%) patients who remained in complete heart block. Thirty patients (70%) remained free of arrhythmia without medication or pacemaker for a mean follow‐up period of 23 ± 13 (2–63) months. Six other patients (15%) were controlled with a previously ineffective medication.

Resynchronization: what if the left ventricular lead cannot reach the lateral or posterolateral wall?

Background: The recommended left ventricular (LV) lead position for cardiac resynchronization therapy (CRT) is at the lateral or posterolateral wall. However, LV leads cannot always be implanted at this site. The objective of our study was to compare the clinical response to CRT when the LV lead could be implanted or not at the lateral or posterolateral wall.

Resynchronization with Left Ventricle Lead Placement Through the Foramen Ovale

Left ventricle (LV) lead placement in a coronary sinus branch for cardiac resynchronization therapy may fail because of anatomical variants, phrenic nerve stimulation, and/or lead instability. We report a case of successful resynchronization from a lead inserted from the left subclavian vein and positioned through a patent foramen ovale (PFO). In conclusion, endocardial LV lead insertion through a PFO enables effective resynchronization delivery without the risks associated with a thoracotomy or atrial transseptal puncture. Copyright

Reverse Remodeling with Resynchronization in an Asymptomatic Patient with Dilated Hypokinetic Cardiomyopathy

Cardiac resynchronization therapy (CRT) is a validated treatment for selected heart failure patients who remain highly symptomatic despite optimal drug treatment. Yet there is currently no indication for CRT in patients with few or no symptoms. We report a spectacular “reverse remodeling” effect after CRT in an asymptomatic patient with hypokinetic dilated myocardiopathy who needed pacing for atrio‐ventricular conduction disorder. CRT was chosen to prevent deterioration of left ventricular function by conventional right apical pacing. Thus, CRT could be indicated in patients with hypokinetic dilated myocardiopathy before the appearance of symptoms.

Cardiac Resynchronization Therapy Using a VDD Lead

In heart failure patients with normal sinus node function, cardiac resynchronization therapy can be achieved with only two leads, one VDD type, and one left ventricular. This reduces the number of venous punctures, implanted leads, and possibly operation and fluoroscopic times and complication rates. We present two cases and discuss the advantages and limits of such a procedure.

CRT27: CARDIAC RESYNCHRONISATION THERAPY IN SINUS RYTHM HEART FAILURE PATIENTS USING A VDD LEAD

Purpose of study Single-lead VDD pacing has shown a reduction in operating time and complications compared to the DDD mode. The objective of our study was to evaluate in sinus rhythm (SR) heart failure pts the interest and limits of a simplified CRT procedure with 2 leads, one VDD and one left ventricle (LV). Methods used Over a 1-year period (May 2002-May 2003), 8 consecutive heart failure pts (1/3 of CRT during the period) in SR, received CRT by the implant of a Medtronic InSync 8042 pacemaker with a Medtronic 5038 VDD lead and an LV lead chosen after per-operative coronary sinus angiography. Summary of results The 8 pts (average age 68±9 years, 5 male) were NYHA class III (3 pts) or IV (5 pts) ; the ejection fraction was 25±3 %. Six pts were primo-implants; 2 pts had VDD pacemakers for 3-7 years, upgraded by the addition of an LV lead. A right approach was used for the 2 upgraded pts and a left approach for the 6 others. There was 1 sub-clavian venous puncture for each implanted lead. The VDD lead was positioned at the right ventricular (RV) apex; sensing (p = 1,9±1,3 mV, R= 17±5,4 mV) and RV threshold (0,5±0,2 V) values were deemed satisfactory. All 8 LV leads were Medtronic 4193 placed in LV lateral veins. Mean implant duration was 133±27 mn versus 147±37 mn for a 3-lead CRT. No implant-related complication occured. 1 pt died of non-cardiac causes at M8; after an average 25 (19-31) months of follow-up, 7 pts are still living, 2 in NYHA class III, 5 in class II. Conclusion In heart failure patients without sinus dysfunction, 2-lead CRT with one VDD lead is achievable. With good atrial sensing, the procedure is simplified thus sparing venous capital and reducing implantation times in these fragile patients.